That Time I Got Reincarnated as a Slime Season 4 - Tensei Shitara Slime Datta Ken S4

Synopsis

Granbell Rosso, leader of the Five Elders of the Siltrosso Kingdom and a former hero, and his granddaughter Mariabell Rosso, engage in a fierce battle against Rimuru in the name of protecting humanity. Meanwhile, in El Dorado, the Land of Gold, the Demon Lord Leon has also begun to move secretly for a specific purpose. Amidst this complex web of conspiracies, a hero is about to rise.